1. Field of the Invention
The present invention relates to a test method of operations of an ultrasonograph and an ultrasound probe, and particularly, to a test method of operations of an ultrasonograph and an ultrasound probe that can specify defective parts of the ultrasound probe.
2. Description of the Related Art
An ultrasonograph is widely used as a unit for a noninvasive acquisition of image information of the body.
The ultrasonograph delivers ultrasound transmitted from an ultrasound probe to a target material in a living body and processes a reflected wave from the target material by processing a received signal received by the ultrasound probe to create a diagnostic image.
The ultrasound probe is constituted by an array transducer formed of a plurality of oscillating elements and includes a function for transmitting and receiving ultrasound.
In recent years, the number of constituent elements of the array transducer has been increased to improve the image quality of a diagnostic image, and for example, a 2D array transducer is constituted by 128×128 oscillating elements.
Therefore, a normal operation of the ultrasound probe needs to be checked before starting diagnosis to always use the ultrasound probe in the best condition.
Conventionally, Japanese Patent Application Laid-Open No. 2002-159492 discloses the following ultrasonograph that checks the normal operation of the ultrasound probe.
More specifically, a transmission and reception surface of an ultrasound probe including a plurality of oscillating elements is brought into contact with a reflector, and the probe transmits ultrasound.
The reflector reflects the transmitted ultrasound, and the ultrasound probe receives a reflected wave.
The quality of operation of each oscillating element is determined based on the amplitude and phase of the received signal. Transmission is controlled so that the transmission is not performed to the oscillating element determined to be a defective oscillating element.
As described, the ultrasonograph of Japanese Patent Application Laid-Open No. 2002-159492 in the aforementioned example of the conventional art determines the quality of operation of each oscillating element based on the amplitude and phase of the received signal. However, the ultrasonograph cannot specify whether a defective part of the ultrasound probe is in a transmitting circuit or in a receiving circuit. As a result, an appropriate treatment may not be applied to the defective part after the quality of operation is determined.
Japanese Patent Publication No. 61-9584 discloses an abnormality determination method, in which two ultrasound probes face each other and mutually transmit and receive ultrasound, and whether a defect is in a transmission operation or in a reception operation is specified based on the received signals.
However, the example of the conventional art determines the quality based on the time difference of the received signals and the signal strength, and the quality determination of each oscillating element is inevitable. The example is inconvenient in that a determination cannot be made without two probes.